The invention concerns an injection molding machine comprising a machine frame, a stationary mold mounting plate and a mold mounting plate which is movable by a closure mechanism which is formed for example by a crank drive or a bell crank mechanism, wherein the movable mold mounting plate and the stationary mold mounting plate are connected without beam members exclusively by way of the machine frame so that the closing force which occurs during the closing procedure and the driving-open force which occurs during injection between the mold mounting plates are passed only by way of the machine frame, and comprising a mold height adjustment mechanism.
An injection molding machine of that kind is known from DE 42 30 348 C2.
In that injection molding machine, the drive for the bell crank mechanism is mounted movably, which results in considerable mass movements in the closing and opening procedures.
The object of the invention is to improve an injection molding machine of that kind.
The object according to the invention is achieved in that the closing force is transmitted from the closure mechanism by way of the mold height adjustment mechanism to the movable mold mounting plate.
It is advantageously provided that at least a part of the mold height adjustment mechanism engages the movable mold mounting plate.
An embodiment of the invention provides that the mold height adjustment mechanism includes at least one nut and at least one spindle which are mounted or accommodated in the movable mold mounting plate.
A very compact configuration for the movable mold mounting plate of the mold height adjustment mechanism is achieved in that the at least one nut is rotatably mounted in the movable mold mounting plate and that the at least one spindle projects into a cavity in the movable mold mounting plate.
A further embodiment of the invention provides that the mold height adjustment mechanism is actuated by a motor which is mounted on the movable mold mounting plate, the motor used being an electric motor, preferably a servo motor.